Compromise resisting combination lock



July 23, 1963 H. c. MILLER 3, 7

COMPROMISE RESISTING COMBINATION LOCK Filed Feb. 2, 1962 2 Sheets-Sheet 1 30 25 INVENTOR fikmy J. lid k1 BY W W MS July 23, 1963 H. c. MILLER 3,

COMPROMISE RESISTING COMBINATION LOCK Filed Feb. 2, 1962 2 Sheets-Sheet 2 INVENTOR ATTORNEYS United States Patent 3,098,376 COMPROMISE RESISTING COMBINATION LOCK Harry C. Miller, 24 Seneca Ave., Rochester 21, N.Y. Filed Feb. 2, 1962, Ser. No. 170,618 fllairns. (Cl. 70-333) The present invention relates in general to the art of combination locks, and more particularly to combination locks having a facility associated therewith for resisting compromise of security by radiological techniques.

Locks of the type commonly referred to as combination locks depend for their operation upon the alignment of a plurality of disc-like rotary elements, commonly called tumbler wheels, in a preselected manner to permit retraction of a reciprocative bolt from its projected position. Each tumbler is provided with a peripheral recess, commonly termed a gate, designed to receive a bar or fence normally disposed in overlying relation with the tumbler wheel peripheries and extending from a fence lever which is pivoted or otherwise coupled to a bolt and controls movement of the latter. When the tumbler gates are all disposed in registry with each other and in preselected alignment with the fence, and a driving cam which effects angular adjustment of the tumbler wheels through lostmotion connections and controls the fence lever is adjusted to a selected angular position, the fence may drop into the tumbler gates and permit such an interconnection of the fence lever with the driving cam that limited arcuate movement of the driving cam will impart movement to the fence lever to retract the bolt. The security of such lock-s is dependent upon the fact that the number of orders or permutations of the possible relative positions of the tumbler gates before all of the tumbler gates come into registry with the fence to permit retraction of the bolt is so large that the chance of these gates being aligned by a person not familiar with the combination is negligible.

In recent years, mechanical arrangements have been devised which are reasonably effective to protect the combination lock against mechanical manipulation thereof by unauthorized persons to surreptitiously detect the combination. However, various techniques have been developed in recent years for compromising the security of combination locks in safe-s and other security closures by the use of high-energy radiation. These have been variously termed radiography or radiological techniques and in general involve the production of pictures or other types .of images of the lock works by photographing high-energy radiation which has passed through the lock mechanism. With the developments made in portable radiation sources in recent years, unauthorized persons may enter on the premises containing a security container and by radiological methods determine the combination setting of the lock and secure unauthorized entry to the protected enclosure in a short time without leaving any evidence of compr0 mise of the lock combination.

While various arrangements have been devised for pro teoting the combination lock against compromise of the combination by radiological techniques, none have proved completely successful. Various radiant energy scattering devices have been employed in or in surrounding relation to the combination lock to effect scattering of the radiation and confound the image or photography produced by radiological techniques, but manipulative techniques have been developed to reduce the effectiveness of such pr otective means.

An object of the present invntion, therefore, is the provision of novel means incorporated in the construction of a combination lock for resisting compromise of the security of the lock by radiological techniques.

Another object of the present invention is the provision of a novel combination lock construction wherein a group of false tumbler wheels in addition to the usual working tumbler wheels are provided in operative association with a driving cam in the lock to be angularly adjusted upon rotation of the driving cam so as to confound or confuse radiological pictures of the lock mechanism and render detection of the combination more difficult.

Other objects, advantages and capabilities of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings illustrating one preferred embodiment of the invention.

In the drawings:

FIGURE 1 is a vertical transverse section view of a combination lock constructed in accordance with the present invention;

FIGURE 2 is a horizontal section view taken along the line 2-2 of FIGURE 1;

FIGURE 3 is a rear elevation view of the intermediate casing portion of the combination lock;

FIGURE 4 is a front elevation of the rear cover plate portion; and

FIGURE 5 is a rear elevation of the front casing portion.

Referring to the drawings wherein like reference characters designate corresponding parts throughout the several figures, there is illustrated a combination lock assembly indicated generally by the reference character 10 embodying the present invention including the usual combination lock dial assembly 11 including a dial 122 having an integral knob v13 projecting therefrom adapted to be disposed a-gainst the front face of a safe door, file cabinet drawer front, or other supporting panel, and a lock casing assembly 14 fixed against the inner surface of the supporting panel. The lock casing 14 includes a rear cover plate 15 and a lock casing member 16 together forming a working tumbler casing of generally conventional construction resembling the usual casing of standard combination locks, together with a false tumbler casing 17 which is inteiposed between the working tumbler casing member 16 and the supporting panel.

The working tumbler casing member 16 houses the usual bolt 18 Which is adapted to slide in a suitable guide- Way 19 in one end wall of the casing member 16, the bolt 18 being operated by a fence lever 20' pivotally attached thereto by means of a screw 21. An annular boss 22 projects rearwardly from the front wall 23 of the casing member 16 and surrounds a circular hole 24 extending through the front Wall 23, the annular boss 22 having a pair of arcuate extensions 25 having a slightly larger inner diameter than the diameter of the hole 24. These elements are so shaped and dimensioned as to form an annular seating surface and arcuate guideway surfaces for a driving cam 26 which is threaded and keyed to a conventional driving spindle 27 extending rearwardly from the dial 12. The fence lever 20 is continuously resiliently urged to- Ward the axis of the driving cam 26 by means of a suitable spring (not shown) and is provided with a fence lever nose 28 adapted to normally ride on the periphery of the driving cam 26.

The rear cover plate 15 is provided with a forwardly projecting hollow tumbler post or arbor 29 which is axially aligned with the axis of the driving cam 26 and hole 24. The usual set of three working tumbler wheels 30, 31 and 32 are supported in axially spaced, concentric relation with the axis of the tumbler post 29 to rotate freely on the tumbler post 29, each of the tumblers in the illustrated embodiment being of the conventional type having disengageable rim and hole portions designed to be changed by a combination resetting key. The tumblers each have a peripheral gate or recess 30', 31' or 32', therein to receive the fence or bar 20' projecting from the fence lever 20. Conventional winged flies 33, in the form of annular rings having an outwardly radiating projection and washers, provided between the axially spaced tumblers 30, 31 and 32 and between the forwardmost tumbler 30 and the driving cam 26 are journaled on the tumbler post 29. The radial projections of the flies 33 engage stops on the adjacent tumblers in the usual manner to provide a lost-motion driving connection between the tumblers operatively associated with the flies. The radial projection on the forwardmost fly is designed and positioned so as to be engaged by a rearwardly projecting portion of a driving pin 34 carried by the driving cam 26 to effect rotation of the forwardmost fly 33 and consequent rotation of the forwardmost tumbler 30 in response to rotation of the driving cam 26.

The lock works including the driving cam, tumblers, fence lever and bolt housed within the working tumbler casing defined by the casing member 16 and cover plate in the exemplary embodiment herein illustrated are of the general type disclosed in my earlier US. Patents No. 2,807,954 granted October 1, 1957, or No. 2,575,674 granted November 20, 1951, the driving cam 26 being of the type wherein a peripheral driving cam gate 36 adapted to receive the nose 28 of the fence lever is normally closed by a bridging slide 37. The bridging slide 37 is slidably supported in a guideway provided on the driving cam 26 for movement diametrically of the driving cam between a gate closing position wherein opposite arcuate ends of the bridging slide 37 form continuations of the driving cam periphery and a gate opening position Wherein the driving cam gate 36 is exposed to receive the fence lever nose 28. The bridging slide 37 may be actuated in the manner disclosed in my earlier US. Patents No. 2,807,954 or No. 2,575,674 as for example by a tang 38 supported on the rear end of an inner spindle 39 extending through an axial bore in the driving spindle 27 and actuated by means of a knob 40 on the forward end of the inner spindle 39.

Interposed between the casing member 16 and the supporting panel on which the lock is mounted is the false tumbler casing 17, constructed in the form of a rearwardly opening housing having a front wall 41 and a rearwardly projecting hollow post or arbor 42 on which an additional set of three tumbler wheels 43, 44 and 4-5 and lost-motion coupling flies 46 are journaled for rotation. In the preferred embodiment herein illustrated, the tumbler wheels 43, 44 and 45 are false or non-working tumblers which are similar in configuration and construction to the active or working tumbler wheels 30, 31 and 32 except that they need not have working combination change mechanisms for coupling and decoupling the peripheral rims from the hubs and have a plurality of circumferentially spaced gatings designated a, b and c on each of the tumbler wheels 43, 44 and 45. The false tumbler casing 17 may also support a case-hardened bolt shielding member 47 slidably supported in a slideway in an end wall of the casing 17 in alignment with the bolt 18, which is connected with the bolt 18 to be moved in correspondence with movement of the bolt 18 by suitable means such as the fence lever screw 21 extending through a slot in the front wall of the casing member 16. The bolt shielding member 47 is provided to shield the bolt 18 against sawing or other mechanical destruction of the bolt. An additional driving pin 48 projects forwardly from the driving cam 26 to a position wherein it can engage. the radial projection on the rearmost fly 46 for transmitting angular movement to the false tumbler wheels 43, 44 and 45 through their respective lost-motion connections upon rotaiton of the driving cam 26. This forwardly projecting driving pin 48 in the illustrated embodiment is also angularly spaced from the driving pin 34 so that the false tumblers 43, 44 and 45 are also driven out of phase with the active tumblers 30, 31 and 32.

It will be noted that the tumbler post 42 projecting rearwardly from the front wall of the false tumbler casing 17 is provided with a constricted bore portion 49a for receiving and journaling the driving spindle 27 and an adjoining enlarged bore portion 49b for receiving and journaling the forwardmost part of the driving cam hub 50.

With this construction, it will be apparent that the series of false tumbler wheels 43, 44 and 45 having three tumbler gatings each will be aligned axially with the working tumbler wheels 30, 31 and 32 and will be angularly adjusted to different positions upon rotation of the driving cam 26 in the process of adjusting the working or active tumbler wheels 30, 31 and 32. Thus the false tumbler wheels 43, 44 and 45 will be interposed in the path of any high-energy radiation such as X-rays or the like which is directed generally along the tumbler axis through the lock mechanism in an attempt to produce a radiological picture or image of the lock. The provision of the false tumbler Wheels in such relationship with the working tumbler wheels greatly confounds or confuses any radiograph or radiological image of the lock works, as the periphal gatings a, b and c of the false tumblers 43, 44 and 45 will be imaged in a similar manner to the gatings of the active tumblers 30, 31 and 32 on the radiological picture or image in such a way that the latter cannot be distinguished from the former. Such an arrangement is also of great value in combination locks having a radiation scattering shield carried by the dial spindle for the purpose of defeating or resisting radiological compromise of security as the presence of such false tumbler wheels in conjunction with the active tumbler wheels, when the false tumbler wheels are driven in the normal fashion by lost-motion connections from the driving cam, assists in resisting compromise of the combination by certain radiological inspection techniques designed especially for combination locks having such radiation scattering shields.

While but one preferred example of the present invention has been particularly shown and described, it is apparent that various modifications may be made therein within the spirit and scope of the invention, and it is desired, therefore, that only such limitations be placed on the invention as are imposed by the prior art and set forth in the appended claims.

What is claimed is:

1. In a combination lock of the type having a plurality of peripherally recessed tumbler wheels spaced axially along and in concentric relation with a selected axis, a rotatable driving cam, a bolt, and a fence lever intercoupled with said bolt having a fence overlying and operatively associated with the peripheries of said tumbler wheels, and a driving cam for adjusting said tumbler wheels and actuating said fence lever; the improvement comprising means for confusing radiological images of the lock produced by radiant energy rays passing therethrough generally along said selected axis including a plurality of auxiliary peripherally recessed tumbler wheels of similar configuration and density to said first mentioned tumbler wheels disposed in concentric relation with said selected axis at a position spaced out of operative relation with said fence, and coupling means responsive to angular adjustment of said driving cam for adjusting said auxiliary tumbler wheels concurrently with adjustment of said first-mentioned tumbler wheels.

2. In a combination lock of the type having a drive spindle journaled for rotation about its axis, a first set of peripherally recessed tumbler wheels concentrically supported in axially spaced relation along the spindle axis, a driving cam fixed on said spindle disposed adjacent one of said tumbler wheels, a bolt, a lever for operating said bolt, said lever having fence means thereon overlying and in operative relation with the peripheries of said first set of tumbler wheels, said driving cam having means for adjusting said first set of tumbler wheels in response to rotation of said driving cam and means for actuating said fence lever; the improvement comprising means for confounding radiological images of said first set of tumbler wheels produced by radiant energy rays projecting generally along axes paralleling said selected axis through the combination lock to resist radiological compromise of the lock combination comprising a second set of tumbler wheels disposed in axially spaced concentric relation with said spindle axis and spaced axially from said first set of tumbler wheels, a plurality of lost-motion coupling means for angularly adjusting said second set of tumbler wheels responsive to rotation of one of the tumbler wheels thereof, and said driving cam having means for adjusting said one of said tumbler wheels of said second set to adjust said second set of tumbler wheels in response to rotation of said driving cam during rotation of the driving cam to adjust said first set of tumbler Wheels.

3. In a combination lock of the type having a drive spindle journaled for rotation about its axis, a first set of peripherally recessed tumbler wheels concentrically supported in axially spaced relation along the spindle axis, a driving cam fixed on said spindle disposed adjacent one of said tumbler wheels, a bolt, a lever for operating said bolt, said lever having fence means thereon overlying and in operative relation with the peripheries of said first set of tumbler wheels, said driving cam having means for adjusting said first set of tumbler wheels in response to rotation of said driving cam and means for actuating said fence lever; the improvement comprising means for confounding radiological images of said first set of tumbler wheels produced by radiant energy rays projecting generally along axes paralleling said selected axis through the combination lock to resist radiological compromise of the lock combination comprising a second set of tumbler wheels disposed in axially spaced concentric relation with said spindle axis and disposed along said spindle axis at the opposite side of said driving cam relative to said first set of tumbler wheels, a plurality of lost-motion coupling means for angularly adjusting said second set of tumbler wheels responsive to rotation of the tumbler wheel thereof nearest the driving cam, and said driving cam having means for adjusting said nearest tumbler wheel of said second set to adjust said second set of tumbler wheels in response to rotation of said driving cam in out-of-phase relationship with adjustment of said first set of tumbler wheels responsive to such rotation.

4. A combination lock assembly for resisting compromise of the combination by radiological imaging of the lock with radiant energy rays penetrating the lock comprising a dial, a dial spindle projecting therefrom adapted to project through a supporting panel, a working tumbler casing adapted to be disposed rearwardly of said panel, a plurality of tumbler wheels interconnected by lost-motion drive connections and operatively mounted within said Working tumbler casing, said tumbler wheels each having a peripheral gate therein, a driving cam rotatably supported within said casing and fixed to said dial spindle, a lost-motion driving connection between said driving cam and one of said tumbler wheels, a bolt slidably mounted in said casing, a movable fence lever secured to said bolt for operating the same and having a fence overlying said tumbler wheels and means for selectively engaging the periphery of said driving cam to be activated thereby, a false tumbler casing adapted to be intercoupled with said working tumbler casing, a plurality of false tumbler wheels of similar configuration and density to said first-mentioned tumbler wheels journaled for rotation Within said false tumbler casing about an axis aligned with the axis of said drive spindle and interconnected by lost-motion driving connections, each of said false tumbler wheels having at least one peripheral gate therein, and means intercoupling one of said false tumbler Wheels with said driving cam to eflect a lost-motion driving connection therebetween for angularly adjusting said false tumbler wheels in response to rotation of said driving cam concurrently with adjusting of the first-mentioned tumbler wheels.

5. An accessory for confusing radiographs of combination locks of the type having a lock casing adapted to be disposed rearwardly of a mounting panel, a dial adapted to be supported forwardly of the supporting panel, a drive spindle fixed to the dial and projecting into said lock casing, a plurality of active peripherally recessed tumbler wheels interconnected by lost-motion driving connections and journaled within said casing for rotation about the drive spindle axis, a bolt, a fence lever intercoupled with the bolt having a fence overlying and operatively associated with the peripheries of said active tumbler wheels, and a driving cam fixed to said spindle for adjusting said active tumbler wheels in response to rotation thereof and for actuating said fence lever; the accessory comprising a false tumbler casing adapted to be interposed between said lock casing and the supporting panel in alignment with the lock casing and having an opening for passage of said spindle therethrough, a plurality of peripherally recessed false tumbler wheels interconnected by lost-motion driving connections journaled within said false tumbler casing in axially spaced concentric relation about said spindle projecting therethrough, said false tumbler wheels having a similar configuration and density to said active tumbler wheels, and means providing a lost-motion driving connection between said driving cam and one of said false tumblers for adjusting said false tumbler wheels in response to rotation of the driving cam during adjusting of said active tumbler wheels.

References Cited in the file of this patent UNITED STATES PATENTS 613,585 Miner Nov. 1, 1898 1,928,853 Doenges Oct. 3, 1933 2,856,765 Sreb Oct. 21, 1958 2,938,374 Criscuolo et a1. May 31, 1960 

1. IN A COMBINATION LOCK OF THE TYPE HAVING A PLURALITY OF PERIPHERALLY RECESSED TUMBLER WHEELS SPACED AXIALLY ALONG AND IN CONCENTRIC RELATION WITH A SELECTED AXIS, A ROTATABLE DRIVING CAM, A BOLT, AND A FENCE LEVER INTERCOUPLED WITH SAID BOLT HAVING A FENCE OVERLYING AND OPERATIVELY ASSOCIATED WITH THE PERIPHERIES OF SAID TUMBLER WHEELS, AND A DRIVING CAM FOR ADJUSTING SAID TUMBLER WHEELS AND ACTUATING SAID FENCE LEVER; THE IMPROVEMENT COMPRISING MEANS FOR CONFUSING RADIOLOGICAL IMAGES OF THE LOCK PRODUCED BY A RADIANT ENERGY RAYS PASSING THERETHROUGH GENERALLY ALONG SAID SELECTED AXIS INCLUDING A PLURALITY OF AUXILIARY PERIPHERALLY RECESSED TUMBLER WHEELS OF SIMILAR CONFIGURATION AND DENSITY TO SAID FIRST MENTIONED TUMBLER WHEELS DISPOSED IN CONCENTRIC RELATION WITH SAID SELECTED AXIS AT A POSITION SPACED OUT OF OPERATIVE RELATION WITH SAID FENCE, AND COUPLING MEANS RESPONSIVE TO ANGULAR ADJUSTMENT OF SAID DRIVING CAM FOR ADJUSTING SAID AUXILIARY TUMBLER WHEELS CONCURRENTLY WITH ADJUSTMENT OF SAID FIRST-MENTIONED TUMBLER WHEELS. 